1. Field of the Invention
The invention relates to drop leaf supports. More particularly, the invention relates to a drop leaf support having an integral hinge.
2. State of the Art
Drop-leaf tables are well known in the art. These tables generally include a central rectangular portion which is supported by three or four legs and one or two leaf portions which are hingedly attached to the central rectangular portion. The leaf portions may be rectangular or semi-circular and are designed to assume two positions: a dropped position where the leaf hangs by a hinge approximately ninety degrees downward from the central portion, and a raised portion where the leaf is supported in a substantially coplanar relationship with the central portion. A collapsible supporting device is used to hold the leaf in the raised position.
Traditionally, the leaf supporting device and the leaf hinge were separate members. The leaf supporting device typically included a centrally hinged folding strut which was hingedly coupled to both the leaf and the central portion of the table. Raising the leaf caused the folding strut to open at its central hinge and a assume a generally collinear configuration. Various means, including springs, rods, and cams, were used to maintain the folding strut in its open supporting position. The leaf was lowered to the dropped position by folding the strut, often working against the spring, cam, or other device which was utilized to hold the strut open.
My prior U.S. Pat. No. 2,902,326 discloses a much improved support for a drop-leaf table which included an integral hinge. This hinge type drop-leaf support 10 is shown in prior art FIGS. 1 and 2 and generally includes five parts: two hinge plates 12, 14, a detent 20, a spring 22, and a slotted strut 26. The table hinge plate 12 is hingedly coupled to the leaf hinge plate 14. Both the table hinge plate 12 and the leaf hinge plate 14 are provided with respective depending legs 16, 18. The detent 20 is pivotally coupled to the leg 16 of the table hinge plate 12. The coil spring 22 biases the detent so that its first end 24 abuts the underside of the table hinge plate 12 when the leaf is raised as shown in prior art FIG. 2. The slotted strut 26 is hingedly coupled at one end 28 to the second end 30 of the detent 20. The slot 32 in the strut 26 has a concave portion 33 near its second end 34 and a rivet 36 in the leg 18 of the leaf hinge plate 14 engages the slot 32.
Prior art FIG. 1 shows the support 10 attached to a table 38 having a leaf 40 in the dropped position and prior art FIG. 2 shows the support in the open supporting position where the leaf 40 is raised relative to the table 38. From the foregoing description, it will be appreciated that when the leaf 40 is raised, the rivet 36 in the leg 18 of the leaf hinge plate 14 moves freely through the slot 32 in the strut 26. This causes the strut 26 to pivot relative to the detent 20 and causes the detent to pivot relative to the leg 16 of the table hinge plate 12. The strut 26 is dimensioned such that when the leaf 40 is raised to its substantially coplanar position with the table 38, the rivet 36 in the leg of the leaf hinge plate is aligned with the concave portion 33 of the slot 32. As the spring 22 biases the detent 20 to the position shown in prior art FIG. 2, the strut 26 is also held in a position where it is free to drop relative to the rivet 36. As the strut drops relative to the rivet, the rivet engages the concave portion 33 of the slot where it is prevented from sliding through the slot. Raising the leaf 40 may be accomplished with one hand by lifting the leaf until the strut 26 drops into the rivet engaging position shown in prior art FIG. 2. In order to lower the leaf, the strut is pressed upward toward the leaf 40 so that rivet 36 is again free to slide through the slot 32 in the strut under the action of gravity. To facilitate lowering of the leaf, the strut is provided with a finger flange 42.
While my hinge type drop-leaf support 10 shown in prior art FIGS. 1 and 2 is a great improvement over the more complex devices often used in drop-leaf tables, I have discovered a more improved hinge type drop-leaf support which is just as easy to use but which is simpler and less expensive to manufacture.